To the Editor: We have a number of comments regarding the study by Dr Ling and colleagues,1 which reported that buprenorphine implants had significantly greater efficacy than placebo in treating opioid dependence. First, it is expected that treatment failure and subsequent withdrawal from the study would be more common in the placebo group.2 In the case of treatment failure, the authors considered all the urine samples from the time of withdrawal to be positive for opioids. Because the primary analysis was conducted using an intention-to-treat approach that included all randomized patients, this could have led to erroneously assigning a greater proportion of positive and lesser proportion of negative urine samples preferentially in the placebo group, artifactually inflating the primary outcome difference between the intervention and control groups.